In general, diagnostic detection of biological information such as the body temperature, pulse and blood pressure has been so far performed to examine the physical abnormality based on the physical detection findings. The detection of biological information has been commonly made with a biological information sensor connected to a subject undergoing a medical examination by a physician or nurse. For example, the biological information can be gathered by measuring the body temperature of the subject with a thermometer placed under the armpit of the subject for a few minutes or measuring the pulse or blood pressure over time.
However, the biological information thus obtained by the inspection method as mentioned above is provisional data from which the biological condition of the subject cannot be fully perceived. Therefore, if the subject has subjective symptoms of abnormalities of some sort, there are cases where the physician or nurse cannot find the abnormality of the subject even by reviewing data obtained from biological tests and possibly fails to give an accurate diagnosis. Specifically in a case of irregular heartbeat or heartbeat abnormality, the abnormalities are not always manifested, and there is a possibility of failing to make an exact diagnosis of the abnormalities depending on conditions such as the psychological state of the subject and the time-span of inspection in a brief observation.
Such being the case, it is recommendable to continue observations of a subject with suspected physical abnormalities for a long stretch of time including sleep hours.
For instance, there are several recommended ways to conduct determination of abnormalities by using a small and light-weight biological information sensor attached to the body of the subject and a data analyzing device receiving data detected by the information sensor by wireless radio communication. In this case, there have been some few advances to use a sensor module incorporating the biological information sensor and transmitter and reduce the sensor module in size and weight so as not to cause limitation in physical activity of the subject.
By way of example, Japanese Patent Application Publication HEI 10-155749 discloses a “system for monitoring and informing about human health conditions” using a life sensor attachable to the human body to measure information on a living body such as pulse, motion, sounds and body temperature in real time. This conventional system is operated in conjunction with a system for alerting a caretaker on the basis of the information detected by the life sensor. The life sensor may be made like a wristwatch and incorporate a communication means, in concert with which a monitoring center is provided with a counterpart communication means to call back.
An “abnormal symptom detector and abnormality warning system” disclosed in Japanese Patent Application Publication No. 2000-93398 is provided with a skin stretch-shrink detection sensor for detecting the stretching and shrinking of the skin associated with pulsebeat and breathing, and an alert circuit for warning of an abnormality when detecting the abnormality. As the skin stretch-shrink detection sensor, a strain gauge is used. A telephone communication system is taken advantage of when detecting any abnormality.
Further, an “emergency relief system” disclosed in Japanese Patent Application Publication HEI 6-242206 has a sensor incorporated therein or connected thereto for detecting pulse, blood pressure and body temperature. This system incorporates a wristwatch transmitter capable of emitting faint radio waves, a receiver for receiving the emergency radio waves from the transmitter, a radio relay device having functions of transmitting and receiving the emergency radio waves, and a radio station for detecting the position of the radio relay device from the emergency radio waves from the radio relay device.
Japanese Patent Application Publication No. 2001-353130 discloses a “physical information detector” having a housing case incorporating a sensor for detecting the physical information and an output means. This detector is formed in a bow so as to be detachably retained on the auricle of a measuring subject. The detector of the same type may be formed like a pendant.
Japanese Patent Application Publication No. 2003-24287 discloses a monitoring device for body conditions, which includes a movement sensor (for measuring at least one of acceleration velocity and angular velocity), and a pulse sensor, so that the body conditions can be monitored by computing data from the sensors. The sensor for detecting the angular velocity is a gyro for detecting the angular velocity of the movement about the Z-axis perpendicular to the longitudinal direction and transverse direction of the superior or inferior limb, which is attached to the superior limb or inferior limb of a living body. The monitoring device further has pulse calculating means with denoising means for filtering out noises in the output from the pulse sensor when issuing pulse output from the acceleration sensor.
The measuring devices according to the conventional technologies described above all are featured by the form and shape of each sensor, detecting method, communication means and emergency system and in that the biological information sensor (including a thermometer, pulse sensor and/or blood pressure meter) is placed at one location of the body of the subject being monitored to collect the biological information. However, the conventional measuring devices generally check up on whether the measurement results obtained from the biological information thus detected for making abnormality determination fall within a predetermined normal range (e.g. body temperature of 36.0° C. to 36.9° C., pulsebeat of 60 to 80 beats per minute, systolic blood pressure of 100 to 120 mmHg, and diastolic blood pressure of less than 80 mmHg may be roughly determined as the basis for average adults at rest.)
However, the conventional methods have a common major problem. That is, it is not always possible for the conventional methods to detect some kinds of abnormalities from the biological information obtained from only one portion of the living body, although some abnormalities may be recognized on the basis of the biological information detected from more than one portion of the living body.
For instance, a physical abnormality may not appear in body temperature on one of the right and left sides of the body, even if an abnormality in body temperature on the other side of the body appears. In such a case, the side of the body, which has abnormal body temperature, may not possibly be diagnosed as the physical abnormality. In fact, there is a case where only the body temperature on one side of the body, which is getting paralyzed, is reduced before the subject who undergoes any diagnosis and is developing disorder is aware of a subjective symptom during a precursory symptom of cerebral infarction, whereas the body temperature on the other nonparalyzed side of the body may change little within the normal range. The physical abnormalities cannot be assuredly recognized by one-point measurement for biological information in which the biological information is detected at one portion of the subject body, possibly resulting in retarding early detection of dangerous diseases.
The physical abnormalities do not appear on both the right and left sides of the body as abnormalities in physical information (e.g. body temperature), but they may sometimes appear as a difference in physical information on both sides of the body (e.g. difference in body temperature). For instance, there may possibly be a difference in body temperature between the right and left sides of the body due to the abnormality of the body in spite of both the temperatures taken under the armpit of the right and left sides of the body falling within the normal temperature range when the subject has an abnormality of the body. In such a case, the physical information must be gathered from the multiple loci of the body to find the abnormality promptly.
To be more specific, it was impossible or difficult to recognize a certain type of physical abnormality by the conventional methods in which biological information was generally detected only at one portion of the subject body, to consequently cause delay in finding the abnormality. As a result, the conventional methods could not apply to early treatment upon finding jeopardy of the subject undergoing medical examination at the early stage. For instance, cerebral stroke and myocardial infarction were difficult to find in their early stages on the basis of the biological information such as body temperature detected at only one portion of the subject body.
In the light of the conventional circumstances as described above, the present invention seeks to provide a biological information monitoring system capable of detecting biological information from the multiple loci of the right and left sides of the living body to early determine physical abnormalities with higher accuracy than that of the conventional art.